Control apparatus



Jan. 1, 1929.

. w. G. HORN I CONTROL APPARATUS Filed Aug. 7, 1926 2 Sheets-Sheet 1 INVENTOR [MY/am 6 H0) Jan. I, 1929. 1,696,914

w. G. HORN CONTROL APPARATUS Filed Aug. 1926 2 Sheets-Sheet 2 INVENTOR (MW/5m 6' H007 oRriEY Patented Jan. 1, 1929.

UNITED STATES PATENT OFFICE.

WILLIAM G. HORN, F EDGEWOOD ACRES, PENNSYLVANIA, ASSIGNOR TO WESTING- HOUSE ELECTRIC & MANUFACTURING COMPANY, A CORPORATION OF PENN- SYLVANIA.

CONTROL APPARATUS.

Application filed August 7, 1926. Serial No. 127,728.

being readily and economically manufactured.

I A more specific object of the invention is to provide for limiting the number of times a relay may be operated without being manually reset by an o erator.

Another object o the invention is to facilitate the setting of the relay to operate any predetermined number of times.

It is also an object of the invention to provide means for indicating the number of times a relay has been operated.

Other objects of the invention will, in part, beobvious and, in part, appear hereinafter. i p

' This invention is disclosed in the embodiment thereof shown in the accompanying drawing and comp-rises the structural features and the combination of elements and arrangement of parts which will be exemplified in the construction hereinafter set forth, and the scope of the application of which will be indicated in the claims.

For a fuller understanding of the inven tion, reference may be had to the following detailed description, taken in connection with the accompanying drawing in which;

Fig. 1 is a view, in front elevation, of a relay provided with a locking attachment constructed in accordance with this invention' Fig. 2 is a view, in side elevation, of the locking attachment;

Fig. 3 is a diagram of connections showing how the relay and locking attachment may be connected in a circuit.

Referring now to the drawing, the reference character 10 designates, generally, an overload relay, of any well-known type, mounted on a panel 11. In this particular construction, the overload relay comprises a coil 12 that is disposed on the panel 11 directly above a pivotally mounted armature 13.

As shown, the armature 13 is pivotally mounted at 13' and is disposed in alinement with a switch-actuating rod 14 which extends through the magnet coil 12. In order to set the armature 13 relative to the coil 12, a set screw 15 is adjustably mounted in a. lug 16 that is provided on the relay frame. The setscrew is disposed to engage a depend ng arm 17 on the armature 13.

The relay magnet coil 12 may be connected in its circuit by means of terminal members, such as shown at 18. Since relays of this type are used for motor circuits and the like, the magnet coil 12 is designed to carry heavy currents without excessive heating.

In order to utilize the relay for interrupt- 1ng circuits, upon the fiow of excessive currents, it is provided with switchmembers or disks, such as 19 and 20, which may be connected in a line-switch-coil circuit. In this embodiment of the invention, in order to simplify the construction, the switch members 19 and 20 are mounted on the rod 14: and insulated therefrom in any suitable manner.

The switch member 19 is disposed to seat on contact members 21 and 22, while the switchmember 2O is positioned to engage the contact members 23 and 24. These contact members are provided for connecting the switch members in-the line-switch-actuating circuits. As illustrated, the contact members may be mounted on the panel 11 by means of a plurality of bolts 25, which may also serve as terminals for engaging the circuit conductors.

As shown, springs 26 are positioned on the rod 14 for retaining the switch members 19 and 20 in position. It will be readily understood that the upper spring 26 maybe limited in its upward movement in any suitable manner, such as by providing an extension 27 on the relay frame that extends toward the rod 14. The provision of springs permits a certain movement of the switch a this construction, the locking is effected by a latch 28 which retains the armature 13in its raised position.

As illustrated, the latch 28, which also functions as an armature, is, pivotally mounted at 29 and is so disposed that, when it hangs in its normal position, it will prevent the armature 13 from dropping to its lower position after it has been actuated by the magnet coil 12.

In order to operate the latch 28 to release the armature 13, a coil 30 is provided. The

coil may be energized from any suitable source and, as Wlll be described hereinafte its circuit may be controlled by any suitable manually operable switch.

When overload relays of this type are utilized on street cars and the like with a view to protecting the apparatus, it is sometimes desirable to limit the number of times that they may be reset by an operator. The

provision of means for limiting the numher of times that an overload relay may be set, and the locating of the device in a more or less inaccessible position, suggests to the operator an inspection of the other apparatus on the vehicle before he opens the relay box to reset the relay manually.

The relay attachment provided in this particular case comprises a switch member 7 31 that is CiiSPOSQCl to engage contact members 32 mounted on the relay panel. The purpose of these contact members will be described hereinafter. As illustrated, the switch member 31 is carried by an arm 33, which is pivotally mounted at 34 on an eX- 1 tension 35 of the relay frame.

' bearings 38 that are formed on the eXtenposed In order to actuate the switch member 31, a cam 36, that is carried by a shaft 37, is disposed in alinement with the arm 33. As shown, the shaft 37 is rotatably mounted in mounted on the shaft 37 and is pivotally connected by means of a pin 40 to the rod 14. In order to permit the rod 14 to move freely, slots are provided in thecrank arm 39 in order that the pin 40 may move longitudinally thereof. during the reciprocatory movement of the rod 14. A spring pawl 41 is carried by the crank arm 39 and is disposed to engage the teeth of a ratchet wheel 42, which is fixed to the shaft 37 by means of a set screw 43. I

As illustrated, a knurled hand-piece 44 is mounted on the end of the shaft 37, so that the latter may be actuated manually. Thus the cam 36 may be set by the operator in any desired position relative to the arm 33.

As will be observed, the switch member 31 may be retained in engagement with the contact members 32 by setting the raised or projecting portion 45 of the cam 36 to engage the arm 33. Further, the arm 33is retained continually in engagement with the cam 36 by means of a spring 46, which is interposed between the lower end of the arm 33 and a projection 47 that is provided on the relay frame.

It will be readily understood that the number of times the relay may be reset by means of the coil 30 will depend on the relation that the distance between the teeth of the ratchet wheel 42 bears to the arc of a circle through which the raised portion 45 of the cam extends.

In order to fa ciliate the setting of the cam the cam is set relative to a selected gradu'ation mark on the disc 49, and the zero on the disc is set to coincide with a mark on the bearing 38, the relaymay be reset a predetermined number of times and the number will be indicated by the disc 48.

' In order that the functioning of the relay and the attachment may be more clearly understood, its operation when connected in a simple circuit, such as shown in Fig. 3, will now be described. In the circuit diagram illustrated, the relay coil 12 is connected 'in series relation with a driving motor 52 by means of a conductor 53.

In order to interrupt the motor circuit in case of an overload caused, for instance, by a short-circuit, two circuit-breakers or line switches 54 and 55 are connected in the conductor 53. These circuit-breakers are normally retained open by springs 56 and may be actuated to'their closed positions by coils 57 and 58, respectively.

The coils 57 and 58 may be energized from any suitable source of current supply and, in this particular circuit, they are disposed to be connected to the trolley line 60 upon the actuation of an auxiliary drum 61, which may be operated in conjunction with the customarily provided master controller. The circuits established for effecting the energization of the coils 57 and 58 extend through conductor 62 leading from the trolley-pole 63 to a contact segment 64 of the drum 61,

meager-.4:

and then through conductois and 66' to the coils 57' and 58, respectively; to ground at 74. Therelay switch members 19 and 20 are connected in the conductors 65' and 66;

The relay coil- 30 may be energized fronr tendingbetween the battery and the coil 30,

has-a gap 7 0 therein which maybe bridged bya contact segment 67' carried by the auxiliary drum 61, in its off position. Consequently, the circuit of the coil 30 cannot be closed unless the drum 61 is in its off position when the contact segment 67 will bridge gap- As shown, a manually" operable switch 68 is connected in the conductor 69 toprovide means for the manual control of'the energization of the coil 30; Therefore, when the drum 61 is in its 'ofi position, by

closing the switch 68, a circuit may be established from the battery 59, through contact segment 67 bridging gap 70, conductor 69, switch 68, resistanceunit 71, coil 80, conductor 72, and contact members 32, which are bridged by switch member 31, to ground at 73.

Assume that the circuit-breakers 54 and 55 have been closed through the operation of the drum 61 and that the motor 52 is in operation. If a short-circuit occurs, so that an excessive current flows in the motor circuit, the coil 12 functions to actuate the armature l3, which swings upward and strikes the switch-actuating rod 14. The switch members 19 and 20 are raised, and the circuits through the actuating coils 57 and 58 are thus opened. Accordingly, the line switches or circuit-breakers 54 and 55 are dropped out, and the motor circuit is broken.

When the armature 13 swings upward, it is locked in its raised position by the latch 28. In this manner, the switch members 19 and 20 are retained in their raised positions so that the motor circuit cannot be closed until the armature 13 is released.

In order to close the circuit provided for energizing the coil 30, the auxiliary control drum 61 is first thrown to its off position to cause the contact segment 67 to bridge the gap 70; then, upon the closure of the switch 68, current flows in the circuit of the coil 30, which has already been traced, and the latch 28 is actuated to release the armature 13. The switch members 19 and 20 are then moved to closed positions, by reason of their own weight.

Each time the switch-actuating rod 14 is raised, the spring pawl 41 carries the ratchet-wheel 42 one step forward, thereby rotating the cam 36. WVhen the rod 14 drops to its lower position, the pawl 41 ,is drawn backward over the ratchet wheel 42: to engage the next tooth. In this manner, the cam 36 is advanced step-by-step, as the switch members-19 and 20 areactuatedlVhenthe cam36 has been turned through a predetermined angle, the arm-.33 drops off the raised portion 45 of the cam, and the spring 46 functions to rotate the arm 33 counter-clockwise, asviewed in Fig; 2, thereby actuating the switch member 31' and opening the circuit through whiclrthe coil 30' is energized Therefore, after the switch members 19 and 20 have been actuated: a

predetermined number of times, causing the cam 36' to rotate through a predetermined angle, the latch 28 cannot be again actuated until the camhasbeen reset manually. to:

move the switch member3l into engagement with the contact members 82.

It will be readily understood that, by removing the nut 51, the cam 36-may be set in any desired position relative tothe disc 48-. In this manner, provision may be made for interrupting the reset circuit after any predetermined number of operations of the switch members 19 and 20'bythe relay, for the purpose previously set forth.

\Vhile the illustrated example constitutes a particular embodiment of my invention, I do not limit myself strictly to the details herein shown, since, manifestly, the same may be considerably varied without departing from the spirit of the invention as defined in the appended claims.

I claim as my invention:

1. The combination with a relay provided with a switch, of means for locking the switch in a predetermined position, means for releasing the switch, and means positively actuated by the switch for rendering the releasing means inoperative.

2. The combination with a relay, of aswitch, actuating means for the switch, means for lockingthe switch against operation, means for releasing the switch, and means disposed for operation by the switchactuating means to render the releasing means inoperative.

The combination with a relay, of a switch member disposed for actuation by the relay, means for locking the switch in a predetermined position, means for releasing the switch, and means positively actuated by the switch,.for rendering the releasing means inoperative after a predetermined number of operations.

4. The combination with a relay, of a switch member disposed for actuation by the relay, means for locking the switch member in a predetermined position, means for releasing the switch member, cam-actuated means for rendering the releasing means inoperative, and means operated by the switch member for operating the cam.

5. The combination with a relay, of a switch member disposed for operation by )the relay, means for locking the switch member, means for releasing the switch member, a second switch for rendering the releasing means inoperative, a cam for actuating said second switch, and means operated in conjunction with the switch member for actuating the cam.

6. The combination with a relay, of a switch'member disposed for operation by the relay, means for locking the switch member in a predetermined position, means for releasing the switch member, a switch for rendering the releasing means inoperative,

pawl-and-ratchet mechanism for rotating the cam adapted to be actuated by the switch member, whereby the cam is advanced stepby-step through the operations of the relay, and means for setting the cam in difierent positions relative to the pawl-and-ratchet mechanism. a g

8. The combination with a relay, of a switch member disposed for operation by the relay, means for locking the switch member against operation, means for releasing the switch member, a second switch for rendering the reieasing meansinoperative, a cam for actuating said second switch, a pawland-ratchet mechanism for rotating" the cam adapted to be actuated by the switch member, whereby the cam is advanced step-by steJ throu h the operations of the rela l b r J,

, means for setting the camyin different'positions relative to the pawl-and-ratchet mechanism, and means for indicating the number of times the relay operates.

In testimony whereof, I have hereunto subscribed my name this 5th day of August, 1926.

WILLIAM G. HORN. 

